The Institute for Safe Medication Practices (ISMP);its partners, Outcome Engineering consultants;and community pharmacy practice sites-Walgreens, Kerr Drug, Medicine Shoppe, and Massachusetts General Hospital ambulatory care pharmacies-plan to apply what has been learned from more than a dozen detailed socio-technical probabilistic risk assessment (ST-PRA) models to improve medication safety in community pharmacies through risk informed interventions. We plan to implement three Interventions that were selected because of significant vulnerabilities detected when modeling the dispensing of four high-alert medications: waFOArin, fentanyl patches, methotrexate, and insulin. In brief, we predicted that prescribing errors with fentanyl patches and order entry errors for all drugs reach consumers frequently, as much as 1 per 1,000 prescriptions. Simulations of various interventions in our risk models led to the decision to develop, test, and implement the following interventions: 1) Implement mandatory patient counseling by a pharmacist for all consumers who pick up a prescription for waFOArin, fentanyl patches, methotrexate (MTX), and targeted types of insulin;this is a pre- and post-evaluation study using observational and self-reported data to measure the error-prevention and detection frequency of the intervention;2) Conduct a readiness assessment to prepare for implementation of bar-coding technology in community pharmacies;this study uses a pretest and posttest design to gather self-reported data about the ability of the tool to predict and prevent technology problems related to barcode scanning;and 3) Implement the use of a simplified risk-assessment/risk-intervention scorecard tool for high-alert medications based on ST-PRA models of the pharmacy dispensing process;this descriptive study will offer community pharmacies a method for predicting the current risk, in quantitative measures, of the dispensing process and a "menu" of Interventions (e.g., "If (risk factor) is (increased/decreased) by ___ percent, risk that the error will reach the patient is reduced to ___ percent") that will describe the percent of risk reduction predicted to occur after implementing the intervention. PUBLIC HEALTH RELEVANCE: This study will help to reduce harmful prescribing, dispensing, and self-administration errors with high-alert medications-drugs that have the greatest risk of causing harm when a mistake occurs. The planned interventions will increase consumer knowledge of risks associated with these drugs, thus saving lives and limiting costs associated with the treatment of harmful medication errors. The study also will facilitate successful adoption of bar-coding technology in community pharmacies, as well as offer pharmacists a new tool to predict the risk of a medication error and the interventions that will be most effective in reducing these risks.